Ram raiders stole boxes of mobile telephones after smashing a stolen car into a shop in Stanmore in the middle of the night.
Four men wearing balaclavas reversed the maroon J-registration Vauxhall Cavalier - earlier stolen from Buckingham Road, Edg-ware - into the front shutters of Carphone Warehouse in The Broadway at 1.40am.
The gang climbed through the splintered shopfront, hoarded goods and loaded the loot into a second car that was waiting nearby with its engine running.
They jumped into the other vehicle, described by police as a sporty BMW or Mercedes, and sped off, leaving the Cavalier embedded into the store.
By daybreak, the store was boarded up and staff were taking a stock audit to discover exactly what the thieves had taken.
Meanwhile, the abandoned Cavalier had been removed to a police pound for forensic examination.
Tuesday's smash-and-grab was the third incident to hit the retailer in the last 12 months.
At 1.05am on March 23, thieves broke in through the window in the roof, ransacked the premises and made off with hundreds of handsets.
They had also made an unsuccessful attempt to break open the store's safe.
In August 2007, two would-be intruders tried to enter the shop from the roof but could not get in.
Harrow Police have made no arrests following this latest break-in.
The Carphone Warehouse refused to comment on either last night's burglary or the previous ones.